Warm-air furnace.



N. FROST.

WARM AIR FURNACE. APPLICATION FILED APR.23, 1915.

- 1,201,033. Patentd Oct. 10,1916.

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' l ATTORNEYS m INVENTOR N. FROST.

WARM AIR FURNACE.

APPLICATION FILED APR.23. 1915.

Patented Oct. 10, 1916.

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A TTOR/VEYS N. FROST.

WARM AIR FURNACE. APPLICATION FILED APR.23.1915.

1,201,033. Patented Oct. 10,1916.

3 SHEETS-SHEET 3.

TED STATES PATENT OFFICE.

NATHANIEL FROST, OF BLOOMINGTON, ILLINOIS, ASSIGNOR T0 AMERICAN FOUNDRY& FURNACE 00., OF BLOOMINGTON, ILLINOIS. i

WARM-AIR FURNACE.

Application filed April 23, 1915. Serial N0. 23,366.

To all whom it may concern:

Be it known that I, NATHANIEL FRosT, a citizen of the United States, anda resident of Bloomington, in the county of McLean .and State ofIllinois, have invented a new and Improved Warm-Air Furnace, of whichthe following is a full, clear, and exact description.

The invention relates to furnaces such as shown and described in theLetters Patent of the United States, Nos. 862,067 and 1,018,967, grantedto me on July 30, 1907, and February 27, 1912, respectively.

The object of the present invention is to provide a new and improvedwarm air furnace more especially designed for use in churches, schoolsand other ,largebuildings and arranged to provide large heating surfacesfor the air to pass over with a view to increase the efficiency of thefurnace, to

relieve the parts of undue strain and to prevent unequal expansion andcontraction in the fire box. A

In order to produce the desired result, use is made of a furnace properhaving a top provided with a smoke outlet adjacent the rear end, aradiator mounted on the said top of the furnace and spaced from thesame, the said radiator having upright air passages for the air to passthrough after the same has passed up the sides and over the top of thefurnace, the said radiator also having longitudinal smoke passages intowhich leads said smoke outlet to cause the smoke and gases from theburning fuel in the furnace to pass through the radiator and thus heatthe air passages and the air passing through the same.

A practical embodiment of the invention is represented in theaccompanying drawings forming a part of this specification, in whichsimilar characters of reference indicate corresponding parts in all theviews.

Figure 1 is a longitudinal central section of the warm air furnace; Fig.2 is a cross section of the same on the line 22 of Fig. 1; Fig. 3 is asectional plan view of the same -on the line 33 of Fig. 1; Fig. 4 is afront elevation of a portion of thefurnace; and Fig. 5 is a sectionalplan view of one of the sides of the fire box, the section being on theline 55 of Fig. 1.

In heating and ventilating churches, schools and other large buildings,it is the practice to employ one or more furnaces or Specification ofLetters Patent.

Patented ca. 10, 1916.

air heaters set up within a casing or brickwork connected by air ductswith a fan or blower employed .for forcing fresh air over the heaters toraise the temperature of the air which latter is then conducted by airlines to the various rooms to be heated.

The warm air in entering a room forces the cold and foul air out throughsuitable vent registers thus insuring proper heating and ventilating ofthe room, and sometimes exhaust fans are employed to facilitate the"heating. and ventilation.

Within the brickwork or casing A is arranged a furnace proper havingafire box B provided with a grate G, and an ash pit D. In theconstruction of the parts mentioned, use is made of a base E containingthe ash pit D and supporting the grate C. The upper ends of the sides ofthe base E support the lower ends of the sides G of the fire box B, andeach of the said sides G is made in sections joined and fastenedtogether at the adjacent side edges by outwardly extending verticalflanges G and bolts G or other fastening devices, asfully shown in .Fig.5. Each of the sections of a side G is corrugated with the corrugationsextending vertically, and the outer faces of the side sections areprovided with vertically disposed integral radiating flanges G The topor roof I of the -fire box B is made in sections corresponding to thesections of a side G, and each top-section is of arch shape andcorrugated so as to present a greater surface against Which the air isforced, and the said sections are joined and fastened together at theiradjacent side edges by transverse flanges I and bolts I. Each topsection is also provided with upwardly extending integralradiatingflanges I whi'ch also add to the heating area. The sides of each topsection are provided with horizontal flanges I resting on and fastenedto corresponding flanges G on the upper ends of the side sections. Bythe arrangement described a large heating surface is provided at thesides G and top I, and the said sides and top are reinforced and bycorrugating the sides, G and top I provision is made for expansion andcontraction thereof to prevent undue straining and cracking of thefurnace. The front sections of the sides G and top I are fastened to thefront B of the fire box B and which front B is attached to the innersurface of the furnace front E The rear sections of the sides G and topI are attached to a box-like breeching J. In order to protect the sidesof the bas E from the heat of the burning fuel on the grate C, use ismade of side linings F in the form of upwardly and outwardly curvedplates, as plainly shown in Fig. 2. The side linings F are spaced fromthe sides of the base E and fit with their upper ends on the lowerportions of the corrugated sides G, and the said linings F form airspaces with the base sides. Air vents E are arranged on the front E, ofthe furnace and lead to the said air spaces to allow cool air to passinto the said air spaces for keeping the upper portions of the sides ofthe base F comparatively cool. The front E is also provided with doors EE leading to the fire box B and the ash pit D, respectively. The

sides G of the fire box B are spaced from' the inner faces of the sidesof the casing A to provide passages for the air passing into the casingA through suitable ductsH opening into the casing A opposite the ash pitD, as plainly indicated in Fig. 2. A blower (not shown) is connectedwith the air ducts H to force the air through the said ducts into thecasing A and against the side walls of the ash pit D and the fire box Bto pass upward over the arched top Ito beheated by contact with the saidsurfaces.

Above the fire box B is arranged a radiator K supported at its rear endon the top of the breeching J and fastened at its for .ward end on thefront E and practically filling the transverse space between the sidewalls of the brick casing A. The radiator K is preferably in the form ofa rectangular box, the underside of which is spaced from the top I ofthe fire box B, as plainly shown in Figs. 1 and 2, so that air passingup on each side of the firebox may pass freely over the entire topthereof and thus insure more complete heating of such air. The radiatorK while practically filling the space laterally between the brick wallsA and thus pre venting any appreciable amount of air passing upward atthe sides is provided with vertically disposed air passages L for thepassage of the air passing up the sides G and over the top I of thefurnace, the radiator projecting laterally beyond the sides of thefurnace and substantially filling from side to side the space above thesame and causing the air arising along the sides of the furnace to bedeflected inwardly and hug and pass entirely over the top of the furnaceand then pass through the radiator, as an escape of air at the sides tothe plenum ereinafter referred to will be effectually prevented. Theradiator K is further provided with forwardly extending smoke passages Nconnected at their rear ends with a smoke outlet 0 arranged in the topof the breeching J. The forward ends of the smoke passages N lead to achamber P in the forward end of the radiator K and from ney. It will benoticed that by this arrangement the smoke and gases passing through thepassages N and Q, heat the air passages L and consequently the airpassing through the same. By reference to Figs. 1 and 2,

it will be noticed that the top of the radiator is a distance from thetop of the casing A to form with the latter a plenum chamber T fromwhich lead'flues U to the different rooms to be heated.

The rear end of the radiator K adjacent to the smoke outlet 0 isconnected by an opening N with the branch passages R and is controlledby a damper V which is normally closed but when opened provides a directpassage for the smoke and gases to pass from the outlet. 0 by way of theopening N and branch passages R into the chimney flue S without firstpassing through the smoke passages N, Q, and R, as previously explained.The damper V is opened whenever it is desired to produce a strong,direct draft in the fire box B and also to reduce the heat of the air.The damper V is provided with a transversely extending shaft V journaledin suitable bearings held on the rear end of the radiator K, and one endof the shaft V extends through a side wall of the radiator K to theoutside thereof. On the outer end of the shaft V is secured an arm Vpivotally connected with a damper rod V extending forwardly through thefront E of the furnace to be within convenient reach of the furnaceattendant to enable the latter to open and close the damper V wheneverit is desired to .do so for the purpose above mentioned.

It will be noted that the damper V is pivot'ed at its lower end along astraight line the upper portion being rounded and that when swungforwardly to close opening N that it rests against the rear wall of theradiator. It is also to be noted when said damper islowered to permittherapid exit of the products of combustion and to produce aquick-draft, that it lies flat within the chimney flue S and that inthis position it will not be afiected to any appreciable extent by heat,and thus burning out of and warping prevented.

A cleaning door E is arranged in the front E opposite the chamber P andthe smoke passages N for conveniently cleaning the same whenever it isdeemed necessary to do so. V

The radiator is to fill practically the entire space between the sidewalls of the casing only sufficient clearance being used to allow forexpansion which will be slight. Having thus described my invention, Iclaim as new and desire to secure by Letters Patent:

1. A warm air furnace and heater-consist ing of a combustion chamberhaving an arched top and a breeching at its rearend, said breechinghaving a smoke outlet, an elongated radiator supported at its rear endon said breeching and having communication, through the same with thesmoke outlet of the combustion chamber, said radiator spaced from thecombustion chamber and ber through the smoke flue, or caused tocirculate forwardly and rearwardly through the radiator.

2. A warm air furnace comprising a combustion chamber having an archedtop'provided with a smoke outlet at its rear end, an elongated radiatorsupported slightly above said chamber and communicating at its rear endwith the smoke outlet of the combustion chamber, said radiator spacedvertically from the combustion chamber and projecting beyond the same atthe sides, said radiator also having a smoke outlet at its rear end, andhaving front and'rear smoke chambers and forwardly and rearwardlyextending smoke passages connecting the smoke chambers, a series oftransverse rows of vertical air passages interposed in said forwardlyand rearwardly extending smoke passages, a smoke flue connecting withthe smoke -'outlet at the rearof the radiator, and a dam- I percontrolling communication betweensaid smoke outlet and smoke fluewhereby direct draft through the smoke flue may be secured andtemperature reduced through the radiator.

3. A warm air furnace structure compris-v ing a casing having air ductsleading into the lower portion thereof and a plenum chamber in its upperportion provided with air ducts for distributing heated air, acombustion chamber" set in said casing, an arched top for saidcombustion chamber, the combustion chamber having corrugated sides and arear breeching provided at its top with a smoke outlet, a radiatormounted on said breeching and coextensive longitudinally with thecombustion chamber and breeching and having its underside spacedtherefrom, said radiator substantially filling from side wall tosidewall of the casing the space above the combustion chamber whereby airascending along the sides of the combustion chamber will be deflectedand caused to hug the arched top before passing through the radiator,said radiator having a 'seriesof rows .of transversely spaced-apartvertical air passages opening into the said plenum-chamber, the radiatorfurther having a horizontal smokejcirculating passage connected atitsoutlet end to the breeching outlet, said air passagesextendingthroughthe smoke circulating passages, and a chimney flue connected with thedischarge end of the smoke circulating passage.

4. In a warm air furnace structure the comblnation with a casing havingcold an ducts leading into its lower portion and a' plenum chamber. inits upper portion provided with ducts for distributing heated air, acast metal combustion chamber having an arched top, an overhead radiatorconnected at its rear end to the rear end of the combustion chamber andspaced therefrom, said radiator and combustion chamber being of generaloblong form, the radiator provided with forward and returnsmoke passagesand aseries of transverse rows of vertical air tubes passing through'sald smoke passages, said radiator substantially filling' from side toside, the space above said combustion chamber, whereby heated airascending along the sides of the combus= tion chamber will be deflectedand caused to hug the arched top and then pass through the radiator intothe plenum chamber, and a smoke outlet flue and a damper controllingcommunication between the combustion chamber, the smoke passages and thesmoke outlet flue. i Y

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

' NATHANIEL FROST. Witnesses:

GUxW. HALEY, J. J. Ka'ms.

